My son's speech was quite slow to develop. He said his first word at 14 months. This was inspite of being taken to numerous baby groups. Infact I think going to all these activities was a mistake as my son got lots of colds and developed glue ear. His speech was very delayed until he had grommets and his adenoids removed at three and half years old.
My daughter is nine months old. We have only had one activity which is a breastfeeding support group. We don't do any music groups, baby swimming or any other fancy activity. We meet other mums at the school pick up and meet people when we take my son to his various activites. Her speech developing really nicely and she has about 5 or 6 words.
I suppose it shows how different boys and girls are. I also think it shows that children develop in their own time. Children do things when they are ready, however hard you work at stimulating them.